Which solvent to use for metal nerves?
Based on this answer on to how to evolve biological radios, the answer states that if creatures in an ecosystem utilize metal for electrical transmission instead the sodium-gate depolarization system used on earth, they would enjoy a considerable speed advantage. Water will dissolve sodium, and potassium, both used in the operation of nerves. This works well on Earth.
But, we aren't on Earth anymore, we are somewhere else; somewhere that the creatures of this place use metals for their nerves (nerves of steel, if you will) instead of sodium and potassium.
- What is the best metal+solvent combination to use for a metal nervous system?
- How likely is this solvent to be freely available in an ecosystem?
Ideally, the metal+solvent pair should not be incompatible with biological systems of the same complexity we see on earth though this need not be proved in your answer.
The design of the surrounding ecosystem is outside the scope of this question. The design of the creatures that would use metal nerves are also outside the scope of this question. We don't care what they look like or how they move. We just care about what they would need to eat and drink to support a nervous system based on metals.